A couple of tire model and size questions (what size with stock gears)

Thanks for looking at this thread and hopefully giving me some good advice.

My wifes Jk is starting to get to the point of needing new tires...the Dueler revo's are nearing their end point 285/70/17 and have been looking again at the REVO, but possibly a 315/70/17 which is the equiv. of a 34" tire

OR

a 33x12.50 General Grabber AT

With the regular JK automatic transmission and 3.73 ratio (I think that is what her 08 has), are the 34's simply too big for that transmission? Will it bog it down too badly and/or do any damage down the road to the transmission/joints or do I simply just need to stick with the current size or a 33" if I want to change up the tire brand/model?

If you have the 3.21 gears, going to 34s will bog it down noticebaly. Regarding lifts, the general consensus is that if you go above 33s you'll need a few inches. By the way, do you have any photos of the current setup?

My advice to the OP is if you don't off road in the mud, I would get the BFG AT KOs they work great in almost all terrains, except deep mud, but the bonus is even if you pay a little more I have seen them go to 70K plus with a tire rotation at every 6K.

The Biggest you want to do on a stock JK is a 33X11.50 or 33X12.50. A 34" on a stock wheel will rub the inner fendor. We have an 07' lifted on 35"'s at it is a dog even with a intake, programmer and exhaust. If you do go to a lift do your self a favor and replace the shafts before you have epic failure.

I am not on stock wheels. I am soft 8's with a little better offset than the stockers have.

I think I am just going to stick with either 33's or the current tire size depending on which tire I go with (either another set of REVO's at the current size - 285/70/17 - or up to a 33" General Grabber AT)

That will keep it from really dogging out the Jeep on the road and since it doesn't do anything tough off road usually. there isn't a big need for bigger right now.